Recent events in Newcastle have highlighted the sometimes controversial question of what force a person can use to protect themselves or their family, particularly when they are threatened within their own home.

In New South Wales there are no specific provisions in the law that deal directly with the amount of force a person can use to protect themselves from an intruder who has entered their home. Instead, the situation is governed by the more general law of “self-defence” that applies in any circumstances where a person feels that they are under threat from another.

The law recognises that there are circumstances where it is legitimate for a person to use force for their own protection, for the protection of others or in order to protect property. This use of force to protect against physical harm or interference with property is commonly known as “self-defence”.

A person who has been charged with a crime involving violence against another is entitled to be found not guilty if they successfully raise self-defence.

The law recognises that a person is allowed to act in self-defence if they are protecting themselves or another person from physical harm. A person can act in self-defence in order to prevent themselves or someone else being illegally kidnapped or held against their will.

Further, the law also recognises that a person can use force to protect their property from being stolen, damaged or destroyed and also to prevent someone from trespassing on their land or to remove a person who is already trespassing.

In considering whether a person’s use of force is justified as self-defence the law looks at two related criteria. Firstly the law asks whether the person actually believed that their conduct was necessary to defend themselves, another person or their property from harm. Secondly, the law asks whether the person’s conduct was actually a reasonable response in the circumstances as they understood them to be.

The first of those questions looks at whether the person was genuinely acting in a belief that the actions they took were needed to defend themselves. The second question requires the law to step away from the subjective belief or opinion of the person involved and ask whether, from an objective viewpoint, what they actually did was a reasonable response to the threat they thought they were facing.

In order to be found not guilty, a person does not have to prove that they were acting in self-defence. Whenever a person is charged with a violent crime and the issue of self-defence is raised the prosecution becomes required to prove that the person’s actions were not done in self-defence.

At a practical level, however, a person who wants to rely on self-defence will need to point to some evidence in the case, or give evidence themselves, that at least raises the possibility that they were acting in self-defence. Unless there is some evidence in the case raising this possibility it is an issue that the court will not need to consider.

Once however the issue of self-defence is raised then the prosecution must prove beyond reasonable doubt that the person was not acting in self-defence. The prosecution can do this by either proving that the person did not believe their actions were necessary OR by proving that the person’s conduct was not a reasonable response to the circumstances as they understood them to be.

Some specific rules apply in cases where a person is charged with causing the death of another person and seeks to rely on self-defence. Firstly, in those cases self-defence cannot be used where death is caused in the course of attempting to protect property, prevent a trespass or remove a trespasser.

Secondly, a person who is charged with murder can rely on a concept known as “excessive self-defence” in order to reduce their culpability for that crime. Excessive self-defence applies where a person causes the death of another person believing their actions to be necessary but the court determines that their actions were in fact not a reasonable response to the circumstances. In a case such as that, the use of “excessive self-defence” reduces the person’s actions from murder down to the crime of manslaughter.

Self-defence is available to be considered in all of the various crimes of violence known to the law, ranging from common assaults right through to crimes such as murder. Any person who is charged with any of these crimes and believes that their actions might be justified on the basis that they were defending themselves, their property or another person should seek legal advice to see whether this defence could be utilised to obtain a not guilty result in the case.